Iranian authorities have detained nearly 100 currency traders and frozen bank accounts worth $5.3 billion in a massive crackdown aimed to stop the slide of the rial, which is already down 10% this year. The police in Tehran said 90 FX dealers were arrested and 10 FX shops were shut down along with the freezing 755 bank accounts. The FT reports that those accounts turned over $5.3 billion last year.

There is a small-scale panic developing in Iran as people rush out of the rial and into U.S. dollars.

The operation was carried out in cooperation with the Central Bank of Iran, which is under fire for the unprecedented growth in the rates of foreign currencies, particularly the U.S. dollar.

Tehran Deputy Police Chief Brigadier General Hossein Rahimi said police forces are maintaining a permanent presence in the foreign currency business district in Tehran and will not allow profiteers to capitalize on the situation. He noted that a high-profile figure dealing in foreign exchange was arrested in the raid.

In a bid to stem the decline, the central bank announced that to encourage savers to keep their money in rials rather buying hard currency, it would ease the cap it imposed in September on the deposit rates offered by lenders, Iranian media reported. Banks will now be able to offer interest rates of up to 20 percent on fixed one-year deposits against 15 percent previously. Authorities also closed the bank accounts of 775 people they suspected of distorting the foreign exchange market with capital movements totaling some 200 trillion rials (more than $4 billion), the government daily Iran reported.

The combination of measures had some success in shoring up the value of the rial — it was changing hands at 47,400 to the dollar on Thursday morning. But it was still a far cry from the 10,000 level it was trading at prior to the tightening of U.S.-led nuclear sanctions in 2012.

According to the country’s real-time data sharing system, SANA, euro valued 59,860 rials in the free market on Tuesday, adding 1.43 percent. The Central Bank of Iran (CBI) put the official rate of euro at 45,539 rials. The USD was quoted at 48,537 rials in the free market gaining 2.56 percent compared to the preceding day. The CBI put the official rate for the greenback at 37,019 rials.

In the meantime, gold coin was traded in Iran at 15,965,000 rials (about $328.9 at the free market rates) on February 13, indicating a rise of 1.4 percent compared to the preceding day. According to data on the website of the Tehran Gold and Jewelry Union, one gram of the 18-karat gold was priced at 1,538,950 rials (about $31.7), growing by 0.69 percent compared to the preceding day.

The development comes as the value market of foreign currencies, especially the greenback, has been rising in the Iranian market recently. Some experts say the rising prices are just a bubble that could soon burst.

The government also says the rise in prices could be psychological and could emanate from citizens’ unwarranted concerns. It says the dollar rate, which currently stands at around IRR 50,000, is surging due to psychological reasons rather than economic factors.

CBI is to issue two different types of foreign exchange bonds in future, the report quoted CBI Governor Valliolah Seif as saying last week.

“CBI will provide investors, who want to invest in foreign currency assets, with suitable options,” he announced at the time, “the bank is also studying possibilities of other regular options including opening currency deposits and other complementary plans.”

Iranian police arrested around 100 money changers on Wednesday as it scrambled to contain the decline of the rial, which has lost a quarter of its value in six months, AFP reported. Tehran’s chief of police, General Hossein Rahimi, told local media that 10 exchange offices had also been shut. Iran’s currency has collapsed from 38,400 rials to the dollar in July to a record low of 48,400 on Wednesday.